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Hi there, I am new to the forum so if this happens to be in the wrong section, sorry for the mix up.

The catalytic converter on my 2004 civic sir ep3 with the 2.0L dohc vtec is plugging up on me and I will have to fix it. I am wondering if it is possible to remove the catalytic converter all together without the check engine light coming on or any other problems?

Any help is greatly appreciated.

 
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Welcome!

Thread moved.


What makes you believe it is plugging up?

A P0420 cat code does not necessarily mean it's plugging up. A cat code only means it's lost efficiency and Oxygen storage capacity.

Removing the cat will cause more cat codes unless you do other things to fool the computer. If your only issue right now is cat code, you could do this already but leave the cat in place. (cheap this way)

Does the car have to pass an emission test?

 
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Thanks for moving my thread to the right section.

I don't have a code reader, and no dash light are coming on, so as far as I know it is not giving any codes. The reason I think the cat is plugging is because there is a rattle that seems to be coming from inside the catalytic converter, and when driving the car it doesn't have the same power on acceleration.

 
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If something inside the cat has come apart bad enough to rattle and cause a restriction, I'd expect it to also set a cat code within a couple "trip cycles".

If I suspected I had an exhaust restriction, there's a couple fairly easy ways to figure out if it's true.

Here's a link: http://www.aa1car.com/library/exhaust_backpressure.htm



Since the front O2 sensor is pretty easy to remove on the majority of Hondas cars, that's my preferred method for checking backpressure directly. I have a gauge setup similar to this:

Your front sensor should be right at the front of the cat though...Under the car.

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A restriction doesn't necessarily have to be a cat problem.
Could your noise be coming from elsewhere under the car, not the cat?
Heat shields DO tend to rust apart and rattle a lot.
Double-wall exhaust pipes can collapse internally and show no outward sign of a problem, resonator/muffler can do similar things internally.
An intake restriction can act very similar to an exhaust restriction too.

 
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I looked at the heat shield and it isn't falling apart or anything. I just thought it was the cat because the rattle started the same time I noticed I was losing power on acceleration. As for the double walled exhaust pipe, would there be any used on my car? I've had the exhaust from the cat back off and that exhaust pipe isn't double walled. Also I have removed the resonator so that isn't a potential problem.

 
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I don't know if yours uses it or not. It was a thought, they can be aggravating as hell to figure out because it's not something you'd expect.

Unbolt the cat from the manifold and see what happens?

 
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Thanks ezone for helping me out with the troubleshooting, I will take the cat off and see what's going on. Thanks again.